Apparatus has heretofore been marketed by applicants' assignee for use as a training aid in theory and operation of hydromechanical fluid power systems. In such apparatus, a plurality of hydromechanical devices, such as fluid-operated hydraulic motors, valves and cylinders, are mounted on a vertical panel carried by a wheeled frame. An hydraulic pump is carried by the frame and selectively connectable by quick-disconnect hoses to one or more of the hydromechanical devices. All components are standard industrial devices with which the laboratory or classroom trainee thus becomes familiar through a series of exercises or problems set by an instructor or instruction manual. For training in electrohydraulics, which represents the current trend in the fluid power industry, an electrohydraulic servo trainer module is provided as a separate unit or as an accessory to the standard hydromechanical trainer.
Although the device described above has met with substantial commercial acceptance and success in both the academic and the industrial training environments, further improvements remain desirable. In particular, current industry trends to electrohydraulics, with a variety of sophisticated electronic control packages, is not well represented in prior art training apparatus. Further, where electrohydraulic trainer packages, such as the servo trainer module discussed above, have been provided as either a separate module or as an accessory to the standard hydromechanical trainer, the electronic control package has not been structured to provide maximum instructional assistance to the trainee, and has not been as well coordinated as desirable with the field manuals associated with the control electronics so that the trainee can become thoroughly familiar with the control electronics in the type of environment as will be encountered in the field.
Thus, there is a need in the art for training apparatus devoted specifically to electrohydraulic control theory and practice, that is versatile in terms of capability for training a student or technician in a wide variety of electronic control techniques, that forms an integral unit with which the trainee can readily become familiar, and in which the electronic control modules are so constructed and arranged as to provide enhanced trainee understanding of electronic control theory and practice, and are closely correlated with standard operator manuals and the like so that the trainee can become familiar with techniques for tailoring control parameters in a manner similar to that which will be encountered in the field. An object of the present invention is to provide an electrohydraulic training unit that fills one or more of these needs in the art.